Hypodermic syringe



July 11, 1957 H. s. cLoYD ETA-.1 3,330,004

HYPODERMIC SYRINGE Filed NOV. 4, 1963 United States Patent O 3,330,004 HYPODERMIC SYRINGE Harold S. Cloyd and Robert T. Mangold, Ilrie, Pa., assignors to N osco Plastics, Incorporated, Erie, Pa., a corporation of Pennsylvania Filed Nov. 4, 1963, Ser. No. 321,075 6 Claims. (Cl. 18-36) This invention is intended to simplify the molding and improve the operation of one time user plastic hypoderniic syringes. A straight needle is loaded into the mold with opposite ends received in complementary parts of the mold forming the hub. A transverse plunger bends the needle intermediate in its ends and plastic is then injected. The bend holds the needle in the hub under the pull yforces arising during use.

In the drawing, FIG. 1 is a section through a hypodermic syringe, FIG. 2 is a section through a mold cavity, and FIGS. 3 and 4 are sections through modifications.

In the drawing, 1 indicates the barrel, 2 the needle hub, 3 the needle, and 4 the plunger. The barrel and hub are preferably molded -of clear rigid plastic such as polystyrene, but may be molded of less rigid plastics. The plunger is preferably molded of a flexible plastic such as polyethylene. Integral angular ribs 5 on the plunger provide a seal and eliminate the need .for the usual rubber piston rings. The needle 3 has a bend 6 which anchors it in the hub Iunder any pull arising during use. The outer end of the needle is protected by the usual needle guard 7.

The mold comprises a stationary part 8 having a cavity 9 for the hub and a bore 10 for the needle. Closing against the part 9 is a part 11 having a cavity 12 for the barrel. The part 11 opens and closes as indicated by the arrow 13. The part 14 carrying a core pin 15 is movable in the direction of arrow 16a. During the initial opening of the mold, the parts 11 and 14 move together. When the needle hub is withdrawn from the cavity 9, movement of the part 11 is stopped and the continued opening movement of the part 14 withdraws the molded piece which is shrunk on the core pin. The core pin has a bore 16 in line with bore 10.

The needle is loaded in the bore 10 while straight. A chamfer 17 guides the needle into the Ibore. When loaded, the needle is accurately held and positioned so that when the mold is closed, the other end is received in the bore 16. The chamfer 18 guides the needle into the bore 16.

After the mold is closed opposite ends of the needle are firmly held in the bores 10 and 16 and an intermediate section 19 of the needle is opposite a plunger 20 guided plunger 22 may remain vanced position during injection, before injection of the plastic.

The mold of FIG. 3 is the same as FIG. 2 except that in the mold part 8a there are two plungers 23 and 2A arranged on opposite sides of the intermediate section 19 `of the needle. After the mold is closed, the plunger 23 is moved to the dotted line position where its inner end 25 is in line with the bore 10. The plunger 24 is then advanced and the needle is supported at one end by the bore 16 and at the opposite end lby the bore 10 and by the inner end 25 of the plunger 23. Advancement of the plunger 24 bends the needle as indicated by dotted lines in the adit is usually retracted 3,330,004 Patented July 11, 1967 26. The bend 26 has the same anchoring effect as the bends 22. The straight section 27 where thelneedle rests on the end 25 of the plunger 23 assists in maintaining the needle point centered in the hub 2 of the syringe. Having the needle point centered in the hub makes the syringe as` to use.

e 'liste mold lof FIG. 4, like the -mold of FIG. 3, has two plungers 28 and 29 on opposite sides on the intermediate section 19 of the needle. These plungers are simultaneously advanced after the mold is closed, bending the needle to an S-shape 30 which provides additional anchorage desirable for the softer and more exible plastics of which the syringe may be molded.

In all forms of the invention, the molds are easily loaded with straight needles and the bends or kinks are rnade after the mold is closed and opposite ends of the needleare positively held in alignment with each other. The straight needles are easily loaded by automatic loading fixtures so the syringe can lbe lmanufactured at low cost, as is very important in syringes which are to be used once and then thrown away.

What is claimed as new is:

1. A mold for a l'iypodermic vsyringe comprising a first part having a cavity for the hub of the syringe and a first bore at the bottom of the cavity for receiving the pointed end of a needle, a second part having a cavity Ifor the barrel of the syringe, a third part having a core pin with its inner end adjacent the top of the hub cavity and having a second bore coaxial and in line with and spaced from the first bore for receiving the other end of the needle, a plunger transverse to the hub cavity and to the axis of the bores and having its inner end between the bores and movable into the hub cavity to engage and bend the unsupported section of a needle between the bores.

2. The mold of claim 1 having in addition another plunger offset from the first plunger on the diametrically opposite side of the axis of the bores and transverse t-o the hub cavity and to the axis of the bores, said plungers being axially spaced and having inner ends movable into the hub cavity to engage and bend the lunsupported section of a needle between the bores in an S shape.

3. A mold for a hypodermic syringe comprising a first part having a cavity for the hub of the syringe and a first bore at the bottom of the cavity for receiving the pointed end of a needle, a second part having a cavity for the barrel of the syringe, a third part having a core pin with its inner end adjacent the top of the hub cavity and having a second bore coaxial and in line with and spaced from the first bore for receiving the other end of the needle, a plunger transverse to the hub cavity and to the axis of the bores and having its inner end between the bores and movable into the hub cavity to engage and bend the unsupported section of a needle between the bores, another plunger otfset from the first plunger on the diametiically opposite side of the axis of the bores and transverse to the hub .cavity and having its inner end adjacent the bottom of the hub cavity and movable to a position in line with the axis of the bores to support the needle adjacent the bottom of the hub cavity While the first plunger bends the unsupported section of the needle.

4. A mold for the hub of a hypodei'mic syringe with a needle embedded therein which comprises separable first and second mold parts cooperating to form a cavity ncluding the hub portion of a hypoderniic syringe, said parts having means for supporting the ends of a straight needle in the mold parts with the unsupported section of the needle within the hub portion of the cavity, said needle supporting means comprising a first bore in the first mold part on one side of the cavity .for receiving one end of the needle and a second bore formed in a core pin with its inner end adjacent the top of the hub cavity in the second mold part coaxial and in line with and spaced from the rst bore for receiving the other end of the needle, and means for bending the unsupported section of the needle transverse to its length While so supported, said means comprising a plunger transverse to the hub cavity and to the naxis of the bores and having its inner end between the bores and movable into the hub cavity to engage and bend the unsupported section of a needle -between the bores.

S.y The mold of claim 4 having in addition means for holding a yportion ofthe unsupported section of the needle in alignment withrthe axis of the needle while the remainder of the unsupported Section is being bent.

V6. The mold of claim 4 having in Vaddition another plunger offset from the first plunger on the diametrically opposite side of the axis yof the bores and transverse to the hub cavity and to the axis of the bores, said plungers being axially spaced and having inner ends movable into the hub cavity to engage and bend the unsupported section of a needle :between the bores in an S shape.

References Cited UNITED STATES PATENTS 1,692,340 11/ 1928 Lattin 18-42 2,252,054 8/1941 Welch 18-36 2,938,238 5/1960 Gewecke et a1. 264-271 XR 3,089,193 5/1963 Weigand 264-275 XR 3,149,375 Y9/1964YV Gehl 18-36 3,200,486 8/ 1965 Shields 264-271 XR 3,207,832 9/1965 Patti et al. 2674-274 XR 3,209,409 10/ 1965 Grathwohl 18-36y ROBERT F. WHITE, Primary Examiner.

L. S. SQUIRES, G. AUVILLE, Assistant Examiners. 

1. A MOLD FOR A HYPODERMIC SYRINGE COMPRISING A FIRST PART HAVING A CAVITY FOR THE HUB OF THE SYRINGE AND A FIRST BORE AT THE BOTTOM OF THE CAVITY FOR RECEIVING THE POINTED END OF A NEEDLE, A SECOND PART HAVING A CAVITY FOR THE BARREL OF THE SYRINGE, A THIRD PART HAVING A CORE PIN WITH ITS INNER END ADJACENT THE TOP OF THE HUB CAVITY AND HAVING A SECOND BORE COAXIAL AND IN LINE WITH AND SPACED FROM THE FIRST BORE FOR RECEIVING THE OTHER END OF THE NEEDLE, A PLUNGER TRANSVERSE TO THE BUB CAVITY AND TO THE AXIS OF THE BORES AND HAVING ITS INNER END BETWEEN THE BORES AND MOVABLE INTO THE HUB CAVITY TO ENGAGE AND BEND THE UNSUPPORTED SECTION OF A NEEDLE BETWEEN THE BORES. 